1987 Singapore 10c Date Difference - Variety?

That is interesting. The bottom digits look anemic and ugly.

I also see potential traces of doubling. For the upper date I see something peeking out of the top of the 9 and something inside the curl of the 9 and the top of the 8 (and possibly with the other digits). But the under 9 doesn't appear to be the 9 from the lower image.

On the bottom 1 there is something to the left which looks to be the shape of the 1 from the upper image, but that could be my mind misinterpreting random marks. (People are good at finding patterns, even when there aren't any.)

Your pictures are nice, but could you try to get better images? (And I'd prefer two separate images, or the images combined side-to-side.)

I'm going to look for date variations in my Singapore coins and dupes. (But not necessarily today or even this week so don't expect a quick update from me.)